Mass of glucose ( C6H12O6) required to be dissolved to prepare one litre of its solution which is isotonic with 15 g L-1 solution of urea (NH2CONH2) is (Given: Molar mass in g mol-1 C : 12, H : 1, O : 16, N : 14)
- 55 g
- 15 g
- 30 g
- 45 g
Answer
(4) 45 g
Solution
Isotonic solutions (both non-electrolytes) have equal molar concentrations.
Molar mass of urea = 60 g mol-1
C = 1560 = 0.25 mol L-1
Molar mass of glucose = 180 g mol-1
mass of glucose = 0.25 180 = 45 g
Answer: (4)